Registration Dossier

Toxicological information

Repeated dose toxicity: inhalation

Currently viewing:

Administrative data

Endpoint:
repeated dose toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
disregarded due to major methodological deficiencies
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Not conducted to GLP but follows basic scientific principles.

Data source

Reference
Reference Type:
publication
Title:
Particles and SO2 - Synergistic effects for pulmonary damage
Author:
Rylander R and Bergström R
Year:
1973
Bibliographic source:
Proceedings of the 3rd International Clean Air Congress, PA23-A25

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The effect of MnO2 on the respiratory tract was investigated by exposing guinea pigs for 28 days.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): manganese dioxide

Test animals

Species:
guinea pig
Strain:
other: conventional and infection controlled animals were used
Sex:
not specified
Details on test animals and environmental conditions:
TEST ANIMALS
- Diet: ad libitum
- Water: tap water

Administration / exposure

Route of administration:
inhalation: aerosol
Type of inhalation exposure:
whole body
Remarks on MMAD:
MMAD / GSD: > 0.5 µm < 5.0 µm
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- System of generating particulates/aerosols: MnO2 dust was generated in a Rag Pe aerosol generator.
- Air change rate: 4 air changes per hour.
- Method of particle size determination: Royco Model 225 particle counter was used. At 20mg MnO2/m³ approx 600 000 particles per minute were found to be >0.5µm and <5.0µm in diameter.
Duration of treatment / exposure:
28 days
Frequency of treatment:
No data
Doses / concentrations
Remarks:
Doses / Concentrations:
20 mg/m3
Basis:

No. of animals per sex per dose:
No data
Control animals:
yes

Results and discussion

Target system / organ toxicity

Critical effects observed:
not specified

Any other information on results incl. tables

Exposure to MnO2 caused a slight increase in the number of macrophages in the infection controlled group. The number of leukocytes was increased in both types of Guinea-pig. MnO2 caused a slight increase in the irritation score when compared to controls. This was more apparent in infection controlled animals.

Applicant's summary and conclusion

Conclusions:
Effects of MnO2 on the infection controlled group were not observed in the normal animals.